WE DON’T GENERALLY think of interior decorators as particularly concerned with saving their clients money. You don’t go around bidding on $14,000 antique Hungarian chairs or gilding the undersides of piano benches if you’re not working for someone with bottomless bank, right? In fact, designers are frequently asked to keep an eye on the left side of the ledger—without letting any of the cost-cutting show. Here’s how 14 of them deftly maintained high style standards with strategies so economically smart, you can try them yourself.